Wilmot Proviso, 1846, amendment to a bill put before the U.S. House of Representatives during the Mexican War; it provided an appropriation of $2 million to enable President Polk to negotiate a territorial settlement with Mexico. David Wilmot Wilmot, David, 1814–68, American legislator, b. Bethany, Pa. As a Democratic Congressman (1845–51) he became widely known as the author of the famous Wilmot Proviso , which helped build up sectional animosity before the Civil War.
..... Click the link for more information. introduced an amendment to the bill stipulating that none of the territory acquired in the Mexican War should be open to slavery. The amended bill was passed in the House, but the Senate adjourned without voting on it. In the next session of Congress (1847), a new bill providing for a $3-million appropriation was introduced, and Wilmot again proposed an antislavery amendment to it. The amended bill passed the House, but the Senate drew up its own bill, which excluded the proviso. The Wilmot Proviso created great bitterness between North and South and helped crystallize the conflict over the extension of slavery. In the election of 1848 the terms of the Wilmot Proviso, a definite challenge to proslavery groups, were ignored by the Whig and Democratic parties but were adopted by the Free-Soil party Free-Soil party, in U.S. history, political party that came into existence in 1847–48 chiefly because of rising opposition to the extension of slavery into any of the territories newly acquired from Mexico.
..... Click the link for more information. . Later the Republican party also favored excluding slavery from new territories.

Bibliography

See C. W. Morrison, Democratic Politics and Sectionalism (1967).

Wilmot Proviso

(1846) Proposal in the U.S. Congress to prohibit the extension of slavery to the territories. Offered by Rep. David Wilmot (1814–68) as an amendment to a bill that purchased territory from Mexico, it prohibited slavery in the new territory. The proviso provoked a national debate that reflected the growing sectional discord between North and South. Despite repeated attempts, the Wilmot Proviso was never passed by both houses of Congress. Nevertheless, the principle became a basic tenet of the Republican Party.